GB2262026A

GB2262026A - Marine jet wash equipment

Info

Publication number: GB2262026A
Application number: GB9125767A
Authority: GB
Inventors: Charles Robert Duthie Ste Tait
Original assignee: Individual
Current assignee: Individual
Priority date: 1991-12-04
Filing date: 1991-12-04
Publication date: 1993-06-09
Anticipated expiration: 2011-12-04
Also published as: GB2262026B; GB9125767D0

Abstract

Equipment for washing down a marine vessel having an on-board hydraulic system comprises a high pressure sea water pump (32) driven directly from an hydraulic motor (30) of the system. Washing down is effected using sea water drawn into the pump (via filter 33) and augmented with food industry approved chemicals (drawn in on line 36). Sea water is sprayed from a lance (34). <IMAGE>

Description

IMPROVED MARINE EOUIPMENT This invention relates to marine equipment and in particular to improved wash-down equipment for a marine vessel (especially a fishing vessel) which can include a capability of using chemicals (e.g. food industry approved chemicals) in the water used for washing down. The invention can extend to equipment provided on a newly built marine vessel, to equipment provided during refit of an existing marine vessel or as add-on equipment to an existing hydraulic system on a marine vessel which has seen many years' service.

It is known to use high pressure water pumps to supply lances for washing down marine vessels but the prime-movers for such pumps have normally been internal combustion (e.g.

diesel) engines or electric motors. Where limited wash-down requirements exist, such combinations of pumps/prime-movers are acceptable and the fresh water supplies on the vessel may be adequate for the purpose. For a full scale marine wash-down (such as is likely to be required by forthcoming EEC Regulations) which includes the cleaning of fishrooms, conveyors and fish hoppers, for example1 a more powerful combination of pump and prime-mover will be required, together with a pump that can operate on sea water.

This invention seeks to provide improved marine washdown equipment which comprises a high pressure sea water pump coupled to a hydraulic motor.

A hydraulic system is available on most fishing vessels (for example to operate the power block) and this invention in its add-on mode proposes fitting a new hydraulic motor into the existing hydraulic system and coupling the drive shaft of that hydraulic motor directly to the wobble or swash plate of a high pressure water pump whose corrosion resistance is such that it can be used with sea water. The term "high pressure sea water pump" as used herein means a pump capable of pressurising water to at least 500 psi and preferably to 2000 psi, and which can be used, with an acceptable working life, with sea water.

To provide a compact connection between the output shaft of the hydraulic motor and the swash plate of the high pressure sea water pump, it is preferable to modify the shaft end cover of the hydraulic motor to connect directly to the end plate of the high pressure sea water pump and to modify the drive shaft of the hydraulic motor to directly engage the swash plate of the high pressure sea water pump.

However, it is not ruled out that the end plate of the pump can be modified, with or without modifying the shaft end cover, and the drive recess in the swash plate could be modified, with or without modifying the drive shaft of the motor.

The invention also relates to a method of washing down a marine vessel having an on-board hydraulic system, which method comprises driving a high pressure sea water pump directly from an hydraulic motor of the system and washing down the vessel using sea water (optionally augmented with food industry approved chemicals) pumped with the high pressure sea water pump.

The accompanying drawings show, by way of example, one embodiment of marine equipment according to the invention.

In the drawings, Figure 1 shows schematically the hydraulic equipment of a fishing vessel modified in accordance with this invention, Figure 2 is a general view showing the linking of a motor and pump for use with the equipment of Figure 1, and Figure 3 shows the end plate of.. the pump coupled directly to a face plate of the motor and the swash plate of the high pressure sea water pump mounted on the drive shaft of the motor.

Figure 1 shows, in full line, a typical on-board hydraulic system 10 for a fishing vessel including a number of hydraulic motors (only one of which is shown at 11). The motor 11 is primarily provided for operating the power block at the stern of the vessel and is controlled from a controller 12 connected to a pressure line 13, leading from a hydraulic pump 14 driven by a prime mover 18, and to a return line 15 leading to a hydraulic tank 16. The system 10 includes a conventional filter 17 in a suction line 19 of the pump 14, and a main relief valve 20 connected to the tank 16.

Figure 1 also shows at 25 the wash-down equipment to which this invention relates. This equipment comprises a hydraulic motor 30, a high-pressure sea water pump 32, a spray lance 34 attached to a pipe 35 and an inlet line 36 for drawing approved chemicals into a stream of sea water fed to the lance 34. A sea water inlet pipe is shown at 31 and a filter at 33.

To power the motor 30 from the existing hydraulic system 10 the additional members shown in dashed lines in Figure 1 can be used. These members are a change-over valve or high pressure carry-over motor control valve 40, a new pressure line 41, a flow control by-pass valve 42 a return line 43 from the valve 42, a high pressure line 44 from the valve 42 to the hydraulic motor 30 and a new return line 45 from the motor 30.

Figure 2 shows the motor 30 and pump 32 linked together with a venturi induction unit 35 communicating with the line 36.

Figure 3 shows the pump 32 largely disassembled but an end plate 52 of the pump is shown bolted to a faceplate 50 of the motor modified to receive the end plate 52. The swash plate 54 of the pump is shown drivably connected to the end of the drive shaft of the motor 30.

The swash plate 54 is contained in a fluted piston housing 56 of the pump 32 which also contains a piston assembly, the pistons being spring-urged so that their inner ends bear against the swash plate 54.

Thus, when the motor 30 is fed with pressurised hydraulic fluid, it rotates the swash plate which in turn causes the pistons to reciprocate in their respective cylinders to draw sea water into the pump via the inlet 31 and to eject the sea water under pressure through the lance 34. The flow of sea water draws in chemicals, via the line 36 which is connected to the induction unit 35.

Figures 2 and 3 show one form of link between the motor 30 and the pump 32, the faceplate 50 of the motor 30 being machined to provide secure connection directly to the end plate 52 of the high pressure sea water pump 32. This modification in the faceplate ensures direct connection between the motor 30 and the pump 32.

To transmit drive from the motor 30 through to the pump 32, the shaft of the motor has been reduced in diameter and provided with a longitudinal keyway adapted to connect directly into the drive aperture of the swash plate 54 of the high pressure sea water pump. To provide additional length on the drive shaft in order to properly engage with the swash plate, a recess can be cut from the shaft in the region closest to the body of the motor.

It will be appreciated that there are other ways in which a direct connection between a hydraulic motor and a high pressure sea water pump can be made and all such arrangements are intended to be embraced in this invention.

To ensure the pump 32 is proof against the corrosive action of sea water the components which come into contact with sea water are desirably made of stainless steel, brass or bronze and the piston can be of stainless steel coated with a crack-resistant ceramic material. The valve springs and the springs in the venturi induction unit 35 are also suitably of stainless steel.

A typical pressure range for the high pressure sea water pump would be from zero to 2000 psi and a flow rate of some 12 litres of sea water per minute at 2000 psi would be suitable. The motor would typically run at 1500 to 1800 rpm in a hydraulic system operating at 1500 to 2000 psi.

Claims

1. Marine wash-down equipment which comprises a high pressure sea water pump coupled to a hydraulic motor.

2. Equipment as claimed in claim 1, comprising inlet means to draw a chemical into the sea water pressurised in the pump.

3. Equipment as claimed in claim 1 or claim 2, in which the hydraulic motor is coupled directly to the high pressure sea water pump.

4. Equipment as claimed in claim 3, in which the shaft end cover of the motor is connected directly to the end plate of the pump and the drive shaft of the motor directly engages the swash plate of the pump.

5. Equipment as claimed in any preceding claim1 in which components of the pump which come in contact with sea water are made of stainless steel, brass or bronze.

6. Equipment as claimed in any one of claims 1 to 4, in which the motor includes a piston made of stainless steel coated with a crack-resistant ceramic material.

7. Equipment as claimed in any preceding claim, in which the hydraulic motor is in circuit with an existing onboard hydraulic system of the vessel.

8. Marine wash-down equipment substantially as hereinbefore described with reference to the accompanying drawings.

9. A method of washing down a marine vessel having an on-board hydraulic system, which method comprises driving a high pressure sea water pump directly from an hydraulic motor of the system and washing down the vessel using sea water pumped with the high pressure sea water pump.

10. A method according to claim 9, in which the sea water used for washing down is augmented with food industry approved chemicals.

11. A method according to claim 9 or claim 10, in which the hydraulic system operates at 1500 to 2000 psi and the pump delivers sea water at a pressure of 2000 psi.

12. A method of washing down a marine vessel which employs equipment as claimed in any one of claims 1 to 7.

13. A method of washing down a marine vessel with sea water substantially as herein described with reference to the accompanying drawings.

14. Add-on equipment for adapting the hydraulic system of a marine vessel to provide a facility of washing down the vessel with sea water which comprises a hydraulic motor close-coupled to a high pressure sea water pump.

15. Add-on equipment as claimed in claim 14, in which the high pressure sea water pump includes means to draw a chemical into the sea water pumped by the pump.

16. Add-on equipment as claimed in claim 14 or 15, in which the shaft end cover of the motor is connected directly to the end plate of the pump and the drive shaft of the motor directly engages the swash plate of the pump.

17. Add-on equipment as claimed in any one of claims 14 to 15, in which components of the pump which come in contact with sea water are made of stainless steel, brass or bronze.

18. Add-on equipment as claimed in any one of claims 14 to 16, in which the motor includes a piston made of stainless steel coated with a crack-resistant ceramic material.

19. Add-on equipment substantially as herein described with reference to the accompanying drawings.